Time delay in double micro-ring resonator with grating

• The paper have studied the transmission and time delay characteristics of the device with the grating.
• Fast- and slow-light can occur in double ring resonator which contains the grating.
• The paper also study the effect of coupling coefficient on transmission characteristics. The increase of the coupling coefficient can lead to the change of the time delay at various port at the resonant point.

In this paper, using the transfer matrix which is obtained by coupled mode theory, we have studied the transmission and time delay characteristics of the micro-ring resonator with the grating. We find that fast- and slow-light can occur in double ring resonator which contains the grating. We also study the effect of coupling coefficient on transmission characteristics. The results reveal that the increase of the coupling coefficient can lead to the change of the time delay at various ports at the resonant point. Thus by adjusting the frequency of the incident light and selecting the device with different coupling coefficient, we can realize the output of the fast and slow light.